Regarding such a lithium-ion secondary battery, JP 2003-197189 A, for example, discloses a method of manufacturing a negative electrode for the lithium-ion secondary battery. The method of manufacturing the negative electrode includes coating a substrate material with a paste in which graphite powder and a binder agent are dispersed in a solvent. Next, the (002) planes of graphite particles contained in the graphite powder are aligned in the same direction in a magnetic field. Then, in this state, the solvent is removed and the graphite powder is solidified by the binder agent.
According to such a manufacturing method of the lithium-ion secondary battery, the (002) planes of the graphite particles contained in the negative electrode are oriented with each other in the same direction between the graphite particles, and the positive electrode can be disposed in the direction of the (002) planes. For that reason, it is stated that the lithium ions transferred between the negative electrode and the positive electrode can smoothly enter the interspace between the layers from the edge portion of the graphite layer.
Likewise, JP 2003-197182 A, JP 2004-220926 A, and JP H09 (1997)-245770 A, for example, disclose that, in the negative electrode for lithium-ion secondary batteries, graphite particles are magnetic-field aligned to cause the 002 planes of the graphite particles stand upright relative to the negative electrode current collector.